Characterization of phospholipid composition and its control in the plasma membrane of developing soybean root
The phospholipid composition of plasma membrane enriched fractions from developing soybean root and several mechanisms which may regulate it have been examined. Plasma membrane vesicles were isolated from meristematic and mature sections of four-day-old dark grown soybean roots (Glycine max (L.) Merr. Cult. Wells II). Analysis of lipid extracts revealed two major phospholipid classes: phosphatidylcholine and phosphatidylethanolamine. Minor phospholipid classes were phosphatidylinositol, phosphatidylserine, phosphatidylgylcerol and diphosphatidylgylcerol. Phospholipid composition was similar at each developmental stage. Fatty acids of phosphatidylcholine and phosphatidylethanolamine were 16:0, 18:0, 18:2, and 18:3. Fatty acid composition varied with both phospholipid class and the developmental stage of the root. The degradation of phosphatidylcholine by endogenous phospholipase D during membrane isolation indicated that this enzyme might be involved in phospholipid turnover within the membrane. Phospholipase D activity was heat labile and increasing the pH of the enzyme assay from 5.3 to 7.8 resulted in 90% inhibition of activity. The turnover of fatty acids within the phospholipids of the plasma membrane was studied. Mature root sections were incubated with (1-/sup 14/C) acetate, 1 mM Na acetate and 50 ..mu..g/ml chloramphenicol. Membrane lipid extracts analyzed for phospholipid class and acyl chain composition revealed that the long incubation times did not alter the phospholipid composition of the plasma membrane enriched fraction.
- Research Organization:
- California Univ., Davis (USA)
- OSTI ID:
- 5942074
- Country of Publication:
- United States
- Language:
- English
Similar Records
The effect of membrane fluidization on protein kinase C: Inhibition by ethanol and higher alcohols and stimulation by increased lipid unsaturation or addition non-esterified fatty acids
Enzymatic probes of lipoprotein structure. Hydrolysis of human serum low density lipoprotein-2 by phospholipase A/sub 2/
Related Subjects
59 BASIC BIOLOGICAL SCIENCES
ALCOHOLS
AMINES
AMMONIUM COMPOUNDS
BACTERIA
CARBON 14 COMPOUNDS
CARBOXYLESTERASES
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CHEMICAL COMPOSITION
CHOLINE
DRUGS
ENZYME ACTIVITY
ENZYMES
ESTERASES
ESTERS
GLYCINE HISPIDA
HYDROLASES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEGUMINOSAE
LIPASE
LIPIDS
LIPOTROPIC FACTORS
MEMBRANES
MICROORGANISMS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PLANTS
QUATERNARY COMPOUNDS
RHIZOBIUM
ROOTS
TRACER TECHNIQUES